1. Field of the Invention
The present invention relates to an operating condition setting-type microwave oven for which, while a membrane keypad corresponding to a control panel of the microwave oven is being manufactured, in order for a control section to execute a key scanning operation, a contact sheet for confirming a set operating condition of the microwave oven is formed in a predetermined key, so that a user can confirm information according to the set operating condition of the microwave oven, and to a method for setting and for detecting the operating condition thereof.
2. Description of the Prior Art
Generally, a microwave oven is a device which cooks food by using microwaves and is divided into a mechanical-type microwave oven and an electronic-type microwave oven.
The mechanical-type microwave oven operates in such a manner that a user optionally adjusts a cooking time and an output of the microwave through a timer knob and an output control knob in accordance with the food to be cooked, respectively. The electronic-type microwave oven operates in such a manner that after optionally selecting both a cooking menu and a cooking time, a user pushes a start key to manually cook the food or, an after a user selects a cooking menu and pushes a start key, a microcontroller performs a cooking operation according to a cooking menu for a set cooking time.
In the case of the electronic-type microwave oven, the microcontroller automatically performs the cooking operation according to the cooking menu, and interfaces the microcontroller to the user by installing a plurality of keys for selecting the cooking name, the cooking time and a weight of the food in a matrix configuration on a membrane keypad, i.e., a control panel.
Normally, the microcontroller which is connected with a key inputting section and a display unit receives a predetermined key signal from the key inputting section, performs a program responsive to a pertinent key signal, and displays the program on the display unit particularly in the case of the selection of the weight or cooking time.
In the case of the electronic-type microwave oven which adopts the microcontroller, an operating condition of the microcontroller comes to vary according to a weight unit and a commercial alternating current frequency depending on the export regions of the microwave ovens. In order to solve the above problem, the operating condition of the microwave oven is checked by using selection jumpers, i.e., electric wires, which are selectively connected to the ports of the microcontroller. Namely, the microcontroller senses and checks the weight unit and the commercial alternating current frequency in such a manner of connecting or disconnecting the selection jumpers to the voltage lines of the input ports of the microcontroller.
More particularly, when an electric power is provided to the microwave oven, the microcontroller performs the detection program according to the operating condition which is set preferentially. In the case where the selection jumpers are connected to the voltage lines, the microcontroller senses the weight unit and the commercial alternating current frequency as the first weight unit and the first commercial alternating current frequency, e.g., pound and 60 [Hz], respectively. On the contrary, in the case where the selection jumpers are disconnected from the voltage lines, the microcontroller senses the weight unit and the commercial alternating current frequency as the second weight unit and the second commercial alternating current frequency, e.g., gram and 50 [Hz], respectively.
As described above, when sensing the weight unit and the commercial alternating current frequency in response to whether or not the selection jumpers are connected by performing the detection program, the microcontroller sets a pertinent sensed flag and then sets a cooking mode for a general cooking program.
Also, the selection jumper type for a common use of the microcontroller has such problems that the input ports for the selection jumpers on the microcontroller are secured, that a space for installing the selection jumpers on a printed circuit board are necessitated, and that the cost and a number of the manufacturing processes are increased due to the use and the installation of the selection jumpers.